Flexible, kink resistant, fluid transfer hose construction

ABSTRACT

A flexible, kink resistant, fluid transfer hose construction that employs a flexible and abrasion-resistant protective jacket is provided. The protective jacket demonstrates the necessary mechanical properties to be included under a crimped sleeve or collar of a hose coupling, thereby increasing the useful life of the hose by, for example, preventing damaging chemicals from accessing underlying layers at each end of the hose construction.

RELATED APPLICATION

This application claims priority from U.S. Provisional PatentApplication Ser. No. 60/409,708, filed Sep. 9, 2002.

TECHNICAL FIELD

The present invention relates to a flexible, kink resistant, fluidtransfer hose construction that employs a flexible andabrasion-resistant protective jacket that demonstrates the necessarymechanical properties to be included under a crimped sleeve or collar ofa hose coupling.

BACKGROUND ART

Hose assemblies for conveying corrosive or aggressive materials areknown. For automotive applications, these assemblies are typicallyrouted through crowded engine compartments that reach temperaturesranging from −40° C. to 175° C. and carry fluids such as fuel and brakefluid that have the potential to chemically erode, swell or otherwisedegrade the interior of the hose assemblies. Thus, these assemblies haveto be resistant to physical, thermal and chemical degradation. Moreover,these hose assemblies have to resist kinking during installation, useand service.

Hose assemblies that include an inner fluoropolymer (e.g.,polytetrafluoroethylene (PTFE)) tube or cylindrical member surrounded bya loosely to tightly wound metallic (e.g., stainless steel) braid havebeen found to provide these necessary physical characteristics.

Abrasion-resistant materials have been used on these prior art braidedhose assemblies as outer protective jackets for the purpose ofprotecting the metallic braid from e.g. corrosion and road hazards, andfor the purpose of preventing the metallic braid from damaging orphysically eroding nearby components in the engine compartment.

Unfortunately, the jacket materials used on these braided hoseassemblies either do not demonstrate the necessary mechanical propertiesto include the material under the crimped sleeve or collar of a hosecoupling or the jacketed hose assemblies fail to demonstrate thenecessary flexibility and kink resistance.

By way of example, U.S. Pat. No. 5,622,394 to Soles et al. describes aflexible hose assembly comprising a plastic outer coating 54 where it isnecessary to strip the coating 54 back from an end of the hose 32 priorto attaching an end fitting. As will be readily appreciated, abrasivetools used to strip the plastic coating 54 back from this area maydamage the metallic braid. Moreover, such an operation is time-consumingand serves to expose the metallic braid to damaging chemicals at eachend of the hose.

By way of further example, hose assemblies jacketed with HYTREL®polyester elastomers have been subjectively evaluated by automotivesuppliers as being too stiff, while hose assemblies jacketed withDYNEON™ THV melt-processable fluoroelastomers, which are also stiff, areknown to demonstrate poor kink resistance and to have a tendency tobuckle, leading vehicle inspectors to believe that rupture of the hoseis imminent.

A need therefore exists for a fluid transfer hose construction that isflexible and kink resistant and that employs a flexible and abrasionresistant protective jacket that demonstrates the necessary mechanicalproperties to be included under a crimped collar of a hose coupling.

It is therefore a primary object of the present invention to providesuch a hose construction.

It is a more particular object to provide an abrasion resistantthermoplastic elastomeric material having improved flexibility for useas a protective jacket for such hose constructions.

It is another more particular object to provide a flexible, kinkresistant, fluid transfer hose construction and assembly that arejacketed with such a thermoplastic elastomeric material.

SUMMARY OF THE INVENTION

The present invention therefore provides a flexible and abrasionresistant thermoplastic elastomeric material, which is suitable for useas a protective jacket on flexible, kink resistant, fluid transfer hoseconstructions, wherein the thermoplastic elastomeric material comprisesa reaction product of:

-   -   (a) at least one Theologically stable polyamide resin having a        melting point or glass transition temperature of from about        25° C. to about 275° C.;    -   (b) a diorganopolysiloxane gum having a plasticity of at least        30 and having an average of at least two alkenyl groups in its        molecule, wherein the weight ratio of the diorganopolysiloxane        gum to the polyamide resin(s) ranges from about 40:60 to about        75:25;    -   (c) a compatibilizer selected from the group of:        -   i. a coupling agent having a molecular weight of less than            800 which contains at least two groups independently            selected from ethylenically unsaturated group, epoxy,            anhydride, silanol, carboxyl, oxazoline or alkoxy having 1            to 20 carbon atoms, in its molecule,        -   ii. a functional diorganopolysiloxane having at least one            group selected from epoxy, anhydride, silanol, carboxyl,            amine, oxazoline or alkoxy having 1 to 20 carbon atoms, in            its molecule, or        -   iii. a copolymer comprising at least one            diorganopolysiloxane block and at least one block selected            from polyamide, polyether, polyurethane, polyurea,            polycarbonate or polyacrylate;    -   (d) an organohydrido silicon compound which contains an average        of at least two silicon-bonded hydrogen groups in its molecule;        and    -   (e) a hydrosilation catalyst.

The present invention further provides a method for preparing thethermoplastic elastomeric material described above, wherein the methodcomprises: mixing components (a) through (e), wherein components (d) and(e) are present in an amount sufficient to cure component (b); and thencuring component (b).

The present invention also provides a flexible, kink resistant, fluidtransfer hose construction comprising:

-   -   (1) a heat and chemically resistant inner tube; and    -   (2) a flexible and abrasion-resistant protective jacket formed        on the inner tube, wherein the hose construction demonstrates a        flexural modulus at 23° C. (as measured by ASTM D790) of less        than or equal to about 330 megapascals (MPa).

The present invention further provides a hose assembly comprising theabove-referenced flexible, kink resistant, fluid transfer hoseconstruction and coupling means.

Other features and advantages of the invention will be apparent to oneof ordinary skill from the following detailed description andaccompanying drawings.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. All publications, patentapplications, patents and other references mentioned herein areincorporated by reference in their entirety. In case of conflict, thepresent specification, including definitions, will control. In addition,the materials, methods, and examples are illustrative only and notintended to be limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

Particular features of the disclosed invention are illustrated byreference to the accompanying drawings in which:

FIG. 1 is a latitudinal cross-sectional view of the hose construction ofthe present invention;

FIGS. 2 to 4 are latitudinal cross-sectional views of preferredembodiments of the inventive hose construction; and

FIG. 5 is a longitudinal cross-sectional view of the hose assembly ofthe present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The hose construction of the present invention, which demonstrates aflexural modulus at 23° C. (as measured by ASTM D790) of less than orequal to about 330 MPa (preferably, less than or equal to about 320 MPa,and more preferably, from about 200 to about 320 MPa), may be used in awide variety of applications. For example, in addition to staticautomotive applications (e.g., as a flexible component in a rigid brakeline system) and dynamic automotive applications (e.g., as a “jounce” orflexible hose mounted to a wheel on a front steering axle), theinventive hose construction may be used in freezer, refrigerator andair-conditioning systems and in the manufacture of semi-conductors.

Referring now to the drawings in detail, the flexible, kink resistant,fluid transfer hose construction of the present invention is showngenerally at 10. As best shown in FIG. 1, the inventive hoseconstruction 10 is basically comprised of a heat and chemicallyresistant inner tube 12 and a flexible and abrasion-resistant protectivejacket 14 formed on inner tube 12.

The heat and chemically resistant inner tube 12 of hose construction 10can effectively accommodate a wide variety of aggressive or degradingfluids, is such as brake fluids, hydraulic oils and fuels. Inner tube12, which preferably has a wall thickness ranging from about 0.13millimeters (mm) to about 1.9 mm and an inner diameter ranging fromabout 2.5 mm to about 50.8 mm, can be made of any polymeric materialthat is extrudable or moldable and that has a compressive strength (asmeasured by ASTM D695) of from about 3.4 MPa to about 310 MPa. Suchmaterials include fluorocarbon polymers, polyamides, polyethyleneresins, polyesters, polyimides, polypropylene, polyvinylchloride,silicones, and mixtures thereof. Preferably, inner tube 12 is made of afluorocarbon polymer such as PTFE, copolymers of tetrafluoroethylene andhexafluoropropylene (FEP), perfluroalkoxyl resins (PFA) and polymers ofethylene-tetrafluoroethylene (ETFE). PTFE, FEP and PFA are sold by E.I.DuPont De Nemours, Inc., Wilmington, Del., under the trademark TEFLON.ETFE is also sold by DuPont under the trademark TEFZEL. More preferably,inner tube 12 is made of PTFE.

The flexible and abrasion-resistant protective jacket 14 formed on innertube 12 is prepared from a thermoplastic elastomeric material anddemonstrates the necessary mechanical properties to be included under acrimped sleeve or collar of a hose coupling.

As will be readily appreciated, the ability to include protective jacket14 in the crimp zone without promoting buckling along the length of thehose, increases the useful life of the hose by eliminating falseindicators of imminent hose failures and by preventing damagingchemicals from accessing inner tube 12 or a reinforcing or barrier layerat each end of the hose. In addition, the cost of manufacture isdecreased as a result of the elimination of the stripping operation.

In a preferred embodiment, the protective jacket 14 is a flameresistant, thermoplastic elastomeric material formed from optionallycompatiblized polyamide (e.g., nylon) resins. Thermoplastic elastomericmaterials formed from polyamide resins, which are suitable for use inthe present invention, are described in U.S. Pat. No. 6,362,287 B1 toChorvath et al., while thermoplastic elastomeric materials formed fromcompatibilized polyamide resins, which are also suitable for use in thepresent invention, are described in U.S. Pat. No. 6,362,288 B1 to Breweret al.

In a more preferred embodiment, the thermoplastic elastomeric materialused to form protective jacket 14 is a reaction product of:

-   -   (a) at least one rheologically stable polyamide resin having a        melting point or glass transition temperature of from about        25° C. to about 275° C.;    -   (b) a diorganopolysiloxane gum having a plasticity of at least        30 and having an average of at least two alkenyl groups in its        molecule, wherein the weight ratio of the diorganopolysiloxane        gum to the polyamide resin(s) ranges from about 40:60 to about        75:25;    -   (c) a compatibilizer selected from the group of:        -   i. a coupling agent having a molecular weight of less than            800 which contains at least two groups independently            selected from ethylenically unsaturated group, epoxy,            anhydride, silanol, carboxyl, oxazoline or alkoxy having 1            to 20 carbon atoms, in its molecule,        -   ii. a functional diorganopolysiloxane having at least one            group selected from epoxy, anhydride, silanol, carboxyl,            amine, oxazoline or alkoxy having 1 to 20 carbon atoms, in            its molecule, or        -   iii. a copolymer comprising at least one            diorganopolysiloxane block and at least one block selected            from polyamide, polyether, polyurethane, polyurea,            polycarbonate or polyacrylate;    -   (d) an organohydrido silicon compound which contains an average        of at least two silicon-bonded hydrogen groups in its molecule;        and    -   (e) a hydrosilation catalyst.

In yet a more preferred embodiment, the thermoplastic elastomericmaterial is a reaction product of.

-   -   (a) from about 30 to about 60 parts by weight, based on the        total weight of the thermoplastic elastomeric material, of at        least one rheologically stable polyamide resin having a melting        point or glass transition temperature of from about 25° C. to        about 275° C.;    -   (b) from about 40 to about 70 parts by weight, based on the        total weight of the thermoplastic elastomeric material, of a        diorganopolysiloxane gum having a plasticity of at least 30 and        having an average of at least two alkenyl groups in its        molecule, wherein the weight ratio of the diorganopolysiloxane        gum to the polyamide resin(s) ranges from about 40:60 to about        70:30;    -   (c) from about 0.5 to about 5 parts by weight, per 100 parts of        the polyamide, of a compatibilizer selected from the group of        -   i. a coupling agent having a molecular weight of less than            800 which contains at least two groups independently            selected from ethylenically unsaturated group, epoxy,            anhydride, silanol, carboxyl, oxazoline or alkoxy having 1            to 20 carbon atoms, in its molecule,        -   ii. a functional diorganopolysiloxane having at least one            group selected from epoxy, anhydride, silanol, carboxyl,            amine, oxazoline or alkoxy having 1 to 20 carbon atoms, in            its molecule, or        -   iii. a copolymer comprising at least one            diorganopolysiloxane block and at least one block selected            from polyamide, polyether, polyurethane, polyurea,            polycarbonate or polyacrylate;    -   (d) an organohydrido silicon crosslinking compound in an amount        sufficient to provide from about 3 to about 30 moles of SiH        groups per mole of Si-alkenyl groups in component (b), wherein        the organohydrido silicon crosslinking compound contains an        average of at least two silicon-bonded hydrogen groups in its        molecule; and    -   (e) a hydrosilation catalyst in an amount sufficient to provide        from about 0.75 to about 100 parts per million (ppm) of metal        ions based on the total weight of the thermoplastic elastomeric        material.

In a most preferred embodiment, the material used to form protectivejacket 14 is a reaction product of:

-   -   (a) from about 30 to about 60 parts by weight, based on the        total weight of the thermoplastic elastomeric material, of a        mixture of polyamides comprising (I) from about 65 to about 75        parts by weight, based on the total weight of the polyamide        mixture, of a nylon 6 resin; and (it) from about 25 to about 35        parts by weight, based on the total weight of the polyamide        mixture, of a nylon 6/12 resin;    -   (b) from about 40 to about 70 parts by weight, based on the        total weight of the thermoplastic elastomeric material, of a        polydimethylsiloxane material;    -   (c) from about 0.5 to about 5 parts by weight, based on the        total weight of the polyamide mixture, of an epoxy functional        silicone fluid compatibilizer;    -   (d) an organohydrido silicon crosslinking compound in an amount        sufficient to provide from about 3 to about 30 moles of SiH        groups per mole of Si-alkenyl groups in component (b);    -   (e) a hydrosilation catalyst in an amount sufficient to provide        from about 0.75 to about 100 ppm of metal ions based on the        total weight of the thermoplastic elastomeric material;    -   (e) from about 0.4 to about 1.5 parts by weight, based on the        total weight of the thermoplastic elastomeric material, of a        silicone fluid;    -   (g) from about 0.475 to about 0.525 parts by weight, based on        the total weight of the thermoplastic elastomeric material, of        an antioxidant; and    -   (h) from about 0.4 to about 1.6 parts by weight, based on the        total weight of the thermoplastic elastomeric material, of a        colorant.

Exemplary materials for use in this most preferred embodiment areidentified below:

-   -   nylon 6 resin—available from Custom Resins, P.O. Box 46,        Henderson, Ky. 42420, under the trade designation NYLENE®        NX3024F (Dry);    -   nylon 6/12 resin—available from EMS-CHEMIE (North America) Inc.,        2060 Corporate Way, P.O. Box 1717, Sumter, S.C. 29151-1717 USA,        under the trade designation GRILON CR 6S;    -   polydimethylsiloxane material—available from Dow Corning        Corporation, P.O. Box 0994, Midland, Mich. 48686-0994, under the        trade designation SILASTIC® GP-30 silicone rubber;    -   epoxy functional silicone fluid—available from Genesee Polymers        Corporation, G-5251 Fenton Road, Flint, Mich. 48507-4036, under        the trade designation GP-32-SILICONE FLUID;    -   organohydrido silicon crosslinking compound—available from Dow        Corning Corporation under the trade designation SYL-OFF® 7678;    -   hydrosilation catalyst—available from Dow Corning Corporation        under the trade designation SYL-OFF® 4000;    -   silicone fluid—available from Dow Corning Corporation under the        trade designation Dow Corning 200® Fluid, 1000 CST;    -   antioxidant—available from Great Lakes Chemical Corporation, 1-T        Great Lakes Blvd. Hwy 52, N.W., West Lafayette, Ind. 47906-0200,        under the trade designation LOWINOX CA22; and    -   colorant—available from Americhem, Inc., 225 Broadway East,        Cuyahoga Falls, Ohio 44221, under the trade designation        16909-F25 BLACK.

The thermoplastic elastomeric material used to form protective jacket 14may be prepared in accordance with the teachings of U.S. Pat. No.6,362,288 B1. In a preferred embodiment, the thermoplastic elastomericmaterial is prepared by compounding the component mixture in atwin-screw extruder, where components (d) and (e) are present in themixture in amounts sufficient to cure component (b), pelletzing thecompounded mixture, and then vacuum drying the pellets overnight at 80°C. The pellets may then be melt-blended and extruded over inner tube 12and cured to form protective jacket 14. It is noted that protectivejacket 14, upon curing will not adhere to inner tube 12.

The protective jacket 14 preferably has a wall thickness ranging fromabout 0.05 mm to about 2.54 mm and an inner diameter ranging from about3.2 mm to about 19.0 mm or greater.

In a more preferred embodiment of the present invention, the flexible,kink resistant, fluid transfer hose construction 10 comprises: (1) aPTFE inner tube 12; and (2) a flexible and abrasion-resistant protectivejacket 14 that comprises a flame resistant, thermoplastic elastomericmaterial formed from one or more compatiblized polyamide resins.

Hose construction 10 of the present invention may further comprise atleast one reinforcing or barrier layer 16 prepared from reinforcing orbarrier materials loosely or tightly braided, woven or wound about theexterior of inner tube 12. Materials suitable for use in layer 16include metal (e.g., carbon, carbon steel, copper, brass, stainlesssteel and alloys thereof) and non-metal (e.g., polyester, nylon, aramid)reinforcing or barrier materials.

In two such embodiments, which are best shown in FIGS. 2 and 3, layer 16is a barrier layer comprising one or more metal layers laminated to theouter surface of inner tube 12. The metal layer(s), which serves toreduce permeation of e.g. hydrocarbons through hose construction 10, isformed by wrapping a metal strip (e.g., a conversion coated aluminumstrip) around the inner tube 12 to form either a single-walled ordouble-walled metal structure.

Preferably, barrier layer 16 is a single-walled aluminum structureprepared in accordance with the methods described in U.S. Pat. No.5,40,334 to O'Melia et al. and U.S. Pat. No. 5,531,841 to O'Melia et al.

More preferably, barrier layer 16 is prepared by dispersing afluoropolymer in a chromate conversion coating and then by applying theresulting mixture to a strip of aluminum foil having a thickness of fromabout 0.025 to about 2.500 mm. The fluoropolymer/conversion coatedaluminum strip is then either axially or helically wrapped around apreexisting fluoropolymer tube. The resulting construction is thenheated to a temperature of about 350° C. for approximately 3 to 5minutes. In a more preferred embodiment, the axially or helicallywrapped aluminum foil strip is overlapped (e.g., 15 to 50% overlap) tocover any gaps or leak paths in the aluminum foil layer thereby furtherreducing permeation through hose construction 10.

In another embodiment (not shown), layer 16 is a reinforcing layercomprising an interwoven braid or a spiral winding of one or moresynthetic fibrous materials. Such fibrous materials include, but are notlimited to, aramid fibers, polyethylene fibers,poly(p-phenylene-2,6-benzobisoxazole) fibers, polyvinyl alcohol fibers,and mixtures thereof. Aramid yarns or fibers are sold by E. I. du Pontde Nemours and Company, 1007 Market Street, Wilmington, Del. 19898,under the trade designation KEVLAR synthetic aramid fiber, and by TeijinShoji (USA), 42 W 39^(th) St. Fl. 6, New York, N.Y. 10018-3809, USA,under the trade designation TECHNORA para-aramid fiber. Polyethylenefibers are available from Honeywell International Inc., 101 ColumbiaRoad, Morristown, N.J. 07962, under the trade designation SPECTRApolyethylene fiber, and also from Toyobo Co., Ltd., DYNEEMA Department,2-8, Dojimahama 2-chome, Kita-Ku, Osaka 530-8230, JAPAN, under the tradedesignation DYNEEMA SK60 polyethylene fiber.Poly(p-phenylene-2,6-benzobisoxazole) or POB fibers are also sold byToyobo Co., Ltd., ZYLON Department, under the trade designation ZYLONPBO fibers, while polyvinyl alcohol fibers are sold by Kuraray America,Inc., 101 East 52^(nd) Street, 26^(th) floor, New York, N.Y. 10022,under the trade designation KURALON polyvinyl alcohol fibers.

In yet another embodiment, which is best shown in FIG. 4, layer 16 is areinforcing layer comprising an interwoven braid or a spiral winding ofa metal (e.g., stainless steel) wire.

Reinforcing or barrier layer 16 preferably has a wall thickness rangingfrom about 0.025 mm to about 2.000 mm and an inner diameter ranging fromabout 3.2 mm to about 100.0 mm.

Hose construction 10 of the present invention may include additionallayers, which overlie the exterior surface of protective jacket 14. Forexample, in applications requiring higher pressure ratings, hoseconstruction 10 may further comprise one or more additional reinforcingor barrier layers and, optionally, one or more additional flexible andabrasion-resistant protective jackets.

In a preferred process for preparing hose construction 10, a polymericmaterial is extruded to form an inner tube 12 having a wall thickness offrom about 0.13 mm to about 1.9 mm and an inner diameter of from about2.5 mm to about 50.8 mm. A reinforcing or barrier material may then bebraided, weaved or wound about the exterior of inner tube 12 to formreinforcing or barrier layer 16. The pelletized thermoplasticelastomeric material is then melt-blended and extruded onto either theinner tube 12 or the reinforcing or barrier layer 16 and is thencross-linked using known techniques which include chemical and radiationcross-linking methods.

Referring now to FIG. 5, a preferred embodiment of the flexible, kinkresistant, fluid transfer hose assembly of the present invention isshown generally at 18. In a preferred process for preparing thisembodiment of hose assembly 18, a crimp collar 20 is positioned on a cutend 22 of hose construction 10 followed by the insertion of a tube-likefitting 24 into the interior 26 of the inner tube 12. Tube-like fitting24 may be mechanically formed to produce beads or upsets 28 a, 28 b, 28c, along its length either before or after the fitting 24 is insertedinto inner tube 12. As will be readily appreciated, beads or upsets 28a, 28 b, serve to provide resistance to tube movement under internalpressure to the hose 10, while bead or upset 28 c serves as a “stopbead” to ensure the proper depth of insertion of fitting 24 into innertube 12. The crimp collar 20 and fitting 24 are then mechanicallyattached to hose 10 by applying sufficient force to deform the collar 20around the hose 10 and to effect a seal between the outside diameter ofthe fitting 24 and the inside diameter of the inner tube 12. Morespecifically, between from about 27.6 to about 450 MPa of mechanicalpressure is applied to collar 20 via a mechanical swage or crimp processwhich serves to apply pressure through the collar 20 to the intermediatelayer(s) and eventually to the inner tube 12 causing the outsidediameter of the fitting 24 to seal against the inside diameter of innertube 12. The resulting connection has sufficient strength to withstandsevere torsional stresses that can result during handling, installationand service and provides a seal to substantially predude the undesiredand gradual escape of fluids over the lifetime of the assembly. As willbe readily apparent to those skilled in the art, the length of crimpcollar 20 and fitting 24, as well as, the number of beads or upsets 28,may be reduced for lower pressure hose applications.

The hose assembly of the present invention, which comprises hoseconstruction 10 and coupling means, demonstrates a balance of physicalis properties. For example, the inventive hose assembly satisfies theminimum requirements set by the Automotive Industry, namely—(1) tensilepull strength—the ability to withstand a pull of at least about 1445Newtons (N) (325 pounds), preferably, at least about 5382 N (1210pounds), and more preferably, at least about 5471 N (1230 pounds),without separation of the hose from its end fittings (U.S. Department ofTransportation (DOT) Motor Vehicle Safety Specification (MVSS) § 571.106S5.3.4), (2) burst strength—the ability to withstand water pressuresranging from 27.6 to 34.5 MPa (4,000 to 5,000 psi) without rupture (U.S.DOT MVSS § 571.106 S5.3.2), and (3) impulse resistance—the ability towithstand at least 150 hot impulse cycles with a brake fluid heated to atemperature of 143° C. (295° F.). For this test, pressure is applied tothe fluid and the hose at a level of 11 MPa (1600 psi) for one minute,the pressure is then released to substantially ambient pressure for oneminute and the cycle repeated (Society of Automotive Engineers (SAE)J1401).

Preliminary testing of aramid-reinforced PTFE hose assemblies jacketedwith either a HYTREL® polyester elastomer, a DYNEON® THVmelt-processable fluoroelastomer or the silicone elastomeric material ofthe present invention has shown, as set forth below, that the hoseassembly of the present invention demonstrates increased flexibility andimproved tensile pull strength over these prior art hose assemblies.Tensile Pull Strength² Jacket Material Flexural Modulus¹ (Newtons)DYNEON ® THV 490 MPa (71,000 psi) 5337 (1,200 pounds) fluoroelastomerHYTREL ® polyester 331 MPa (48,000 psi) 4537 (1,020 pounds) elastomerInventive Silicone 317 MPa (46,000 psi) 5471 (1,230 pounds) ElastomericMaterial¹ASTM D790 (23° C.)²U.S. DOT MVSS § 571.106 S5.3.4

While various embodiments of the present invention have been describedabove, it should be understood that they have been presented by way ofexample only, and not limitation. Thus, the breadth and scope of thepresent invention should not be limited by any of the exemplaryembodiments.

1. A method for preparing a protective jacket for use on flexible, kinkresistant, fluid transfer hose constructions, wherein the methodcomprises preparing the protective jacket using a thermoplasticelastomeric material that comprises a reaction product of: (a) at leastone rheologically stable polyamide resin having a melting point or glasstransition temperature of from about 25° C. to about 275° C.; (b) adiorganopolysiloxane gum having a plasticity of at least 30 and havingan average of at least two alkenyl groups in its molecule, wherein theweight ratio of the diorganopolysiloxane gum to the polyamide resin(s)ranges from about 40:60 to about 75:25; (c) a compatibilizer selectedfrom the group of: i. a coupling agent having a molecular weight of lessthan 800 which contains at least two groups independently selected fromethylenically unsaturated group, epoxy, anhydride, silanol, carboxyl,oxazoline or alkoxy having 1 to 20 carbon atoms, in its molecule, ii. afunctional diorganopolysiloxane having at least one group selected fromepoxy, anhydride, silanol, carboxyl, amine, oxazoline or alkoxy having 1to 20 carbon atoms, in its molecule, or iii. a copolymer comprising atleast one diorganopolysiloxane block and at least one block selectedfrom polyamide, polyether, polyurethane, polyurea, polycarbonate orpolyacrylate; (d) an organohydrido silicon compound which contains anaverage of at least two silicon-bonded hydrogen groups in its molecule;and (e) a hydrosilation catalyst.
 2. The method of claim 1, wherein theTheologically stable polyamide resin(s) of the thermoplastic elastomericmaterial is present in an amount ranging from about 30 to about 60 partsby weight, based on the total weight of the thermoplastic elastomericmaterial.
 3. The method of claim 2, wherein the Theologically stablepolyamide resin(s) is a mixture of polyamides comprising (i) from about65 to about 75 parts by weight, based on the total weight of thepolyamide mixture, of a nylon 6 resin; and (ii) from about 35 to about25 parts by weight, based on the total weight of the polyamide mixture,of a nylon 6/12 resin.
 4. The method of claim 1, wherein thediorganopolysiloxane gum of the thermoplastic elastomeric material ispresent in an amount ranging from about 40 to about 70 parts by weight,based on the total weight of the thermoplastic elastomeric material, andwherein the weight ratio of the diorganopolysiloxane gum to thepolyamide resin(s) ranges from about 40:60 to about 70:30.
 5. The methodof claim 4, wherein the diorganopolysiloxane gum is apolydimethysiloxane material.
 6. The method of claim 1, wherein thecompatibilizer of the thermoplastic elastomeric material is present inan amount ranging from about 0.5 to about 5 parts by weight, per 100parts of the polyamide resin(s).
 7. The method of claim 6, wherein thecompatibilizer is an epoxy functional silicone fluid compatibilizer. 8.The method of claim 1, wherein the thermoplastic elastomeric materialfurther comprises one or more silicone fluids, antioxidants andcolorants.
 9. The method of claim 1, wherein the thermoplasticelastomeric material is cross-linked.
 10. A flexible, kink resistant,fluid transfer hose construction comprising: (a) a heat and chemicallyresistant inner tube; and (b) a flexible and abrasion-resistantprotective jacket formed on the inner tube, wherein the hoseconstruction demonstrates a flexural modulus at 23° C. (as measured byASTM D790) of less than or equal to about 330 megapascals.
 11. The hoseconstruction of claim 10, which demonstrates a flexural modulus at 23°C. (as measured by ASTM D790) of less than or equal to about 320megapascals.
 12. The hose construction of claim 11, which demonstrates aflexural modulus at 23° C. (as measured by ASTM D790) of from about 200to about 320 megapascals.
 13. The hose construction of claim 10, whereinthe heat and chemically resistant inner tube is prepared from anextrudable or moldable polymeric material that has a compressivestrength (as measured by ASTM D695) of from about 3.4 to about 310megapascals.
 14. The hose construction of claim 13, wherein thepolymeric material is selected from the group of fluorocarbon polymers,polyamides, polyethylene resins, polyesters, polyimides, polypropylene,polyvinylchloride, silicones, and mixtures thereof.
 15. The hoseconstruction of claim 14, wherein the polymeric material is afluorocarbon polymer selected from the group of polytetrafluoroethylene,copolymers of tetrafluoroethylene and hexafluoropropylene,perfluoroalkoxyl resins and polymers of ethylene-tetrafluoroethylene.16. The hose construction of claim 10, wherein the heat and chemicallyresistant inner tube has a wall thickness ranging from about 0.13 toabout 1.9 millimeters, and an inner diameter ranging from about 2.5 toabout 50.8 millimeters.
 17. The hose construction of claim 10, whereinthe flexible and abrasion-resistant protective jacket is prepared from athermoplastic elastomeric material.
 18. The hose construction of claim17, wherein the thermoplastic elastomeric material is formed fromoptionally compatibilized polyamide resins.
 19. The hose construction ofclaim 18, wherein the thermoplastic elastomeric material comprises areaction product of: (a) at least one rheologically stable polyamideresin having a melting point or glass transition temperature of fromabout 25° C. to about 275° C.; (b) a diorganopolysiloxane gum having aplasticity of at least 30 and having an average of at least two alkenylgroups in its molecule, wherein the weight ratio of thediorganopolysiloxane gum to the polyamide resin(s) ranges from about40:60 to about 75:25; (c) a compatibilizer selected from the group of i.a coupling agent having a molecular weight of less than 800 whichcontains at least two groups independently selected from ethylenicallyunsaturated group, epoxy, anhydride, silanol, carboxyl, oxazoline oralkoxy having 1 to 20 carbon atoms, in its molecule, ii. a functionaldiorganopolysiloxane having at least one group selected from epoxy,anhydride, silanol, carboxyl, amine, oxazoline or alkoxy having 1 to 20carbon atoms, in its molecule, or iii. a copolymer comprising at leastone diorganopolysiloxane block and at least one block selected frompolyamide, polyether, polyurethane, polyurea, polycarbonate orpolyacrylate; (d) an organohydrido silicon compound which contains anaverage of at least two silicon-bonded hydrogen groups in its molecule;and (e) a hydrosilation catalyst.
 20. The hose construction of claim 19,wherein the Theologically stable polyamide resin(s) is present in thethermoplastic elastomeric material in an amount ranging from about 30 toabout 60 parts by weight, based on the total weight of the thermoplasticelastomeric material.
 21. The hose construction of claim 20, wherein theTheologically stable polyamide resin(s) is a mixture of polyamidescomprising (i) from about 65 to about 75 parts by weight, based on thetotal weight of the polyamide mixture, of a nylon 6 resin; and (ii) fromabout 35 to about 25 parts by weight, based on the total weight of thepolyamide mixture, of a nylon 6/12 resin.
 22. The hose construction ofclaim 19, wherein the diorganopolysiloxane gum is present in thethermoplastic elastomeric material in an amount ranging from about 40 toabout 70 parts by weight, based on the total weight of the thermoplasticelastomeric material, and wherein the weight ratio of thediorganopolysiloxane gum to the polyamide resin(s) ranges from about40:60 to about 70:30.
 23. The hose construction of claim 22, wherein thediorganopolysiloxane gum is a polydimethysiloxane material.
 24. The hoseconstruction of claim 19, wherein the compatibilizer is present in thethermoplastic elastomeric material in an amount ranging from about 0.5to about 5 parts by weight, per 100 parts of the polyamide resin(s). 25.The hose construction of claim 24, wherein the compatibilizer is anepoxy functional silicone fluid compatibilizer.
 26. The hoseconstruction of claim 19, wherein the thermoplastic elastomeric materialfurther comprises one or more silicone fluids, antioxidants andcolorants.
 27. The hose construction of claim 19, wherein thethermoplastic elastomeric material is cross-linked.
 28. The hoseconstruction of claim 19, wherein the flexible and abrasion-resistantprotective jacket has a wall thickness ranging from about 0.05 to about2.54 millimeters, and an inner diameter ranging from about 3.2 to about19.0 millimeters.
 29. The hose construction of claim 19, wherein theheat and chemically resistant inner tube is prepared from an extrudablepolytetrafluoroethylene material and wherein the flexible andabrasion-resistant protective jacket is prepared from a thermoplasticelastomeric material.
 30. The hose construction of claim 19, whichfurther comprises at least one reinforcing or barrier layer.
 31. Thehose construction of claim 30, wherein the reinforcing or barrier layercomprises one or more metal layers laminated to an outer surface of theinner tube.
 32. The hose construction of claim 30, wherein thereinforcing or barrier layer comprises an interwoven braid or spiralwinding of one or more synthetic fibrous materials selected from thegroup of aramid fibers, polyethylene fibers,poly(p-phenylene-2,6-benzobisoxazole) fibers, polyvinyl alcohol fibers,and mixtures thereof.
 33. The hose construction of claim 30, wherein thereinforcing or barrier layer comprises an interwoven braid or a spiralwinding of a metal wire.
 34. The hose construction of claim 30, whereinthe reinforcing or barrier layer has a wall thickness ranging from about0.025 to about 2.000 millimeters, and an inner diameter ranging fromabout 3.2 to about 100.0 millimeters.
 35. A hose assembly comprising:(a) a flexible, kink resistant, fluid transfer hose constructioncomprising (i) a heat and chemically resistant inner tube, and (ii) aflexible and abrasion-resistant protective jacket formed on the innertube, wherein the hose construction demonstrates a flexural modulus at23° C. (as measured by ASTM D790) of less than or equal to about 330megapascals; and (b) coupling means.
 36. The hose assembly of claim 35,which demonstrates a tensile pull strength (as measured by U.S. DOT MVSS§ 571.106 S5.3.4) of at least about 1445 Newtons.
 37. The hose assemblyof claim 36, which demonstrates a tensile pull strength (as measured byU.S. DOT MVSS § 571.106 S5.3.4) of at least about 5382 Newtons.
 38. Thehose assembly of claim 37, which demonstrates a tensile pull strength(as measured by U.S. DOT MVSS § 571.106 S5.3.4) of at least about 5471Newtons.
 39. A flexible and abrasion resistant thermoplastic elastomericmaterial suitable for use as a protective jacket on flexible, kinkresistant, fluid transfer hose constructions, wherein the thermoplasticelastomeric material comprises a reaction product of: (a) a mixture ofpolyamides comprising (i) from about 65 to about 75 parts by weight,based on the total weight of the polyamide mixture, of a nylon 6 resin;and (ii) from about 35 to about 25 parts by weight, based on the totalweight of the polyamide mixture, of a nylon 6/12 resin; (b) adiorganopolysiloxane gum having a plasticity of at least 30 and havingan average of at least two alkenyl groups in its molecule, wherein theweight ratio of the diorganopolysiloxane gum to the polyamide resin(s)ranges from about 40:60 to about 75:25; (c) a compatibilizer selectedfrom the group of: i. a coupling agent having a molecular weight of lessthan 800 which contains at least two groups independently selected fromethylenically unsaturated group, epoxy, anhydride, silanol, carboxyl,oxazoline or alkoxy having 1 to 20 carbon atoms, in its molecule, ii. afunctional diorganopolysiloxane having at least one group selected fromepoxy, anhydride, silanol, carboxyl, amine, oxazoline or alkoxy having 1to 20 carbon atoms, in its molecule, or iii. a copolymer comprising atleast one diorganopolysiloxane block and at least one block selectedfrom polyamide, polyether, polyurethane, polyurea, polycarbonate orpolyacrylate; (d) an organohydrido silicon compound which contains anaverage of at least two silicon-bonded hydrogen groups in its molecule;and (e) a hydrosilation catalyst.
 40. A method for preparing athermoplastic elastomeric material suitable for use as a protectivejacket on flexible, kink resistant, fluid transfer hose constructions,which comprises: (I) mixing (a) a mixture of polyamides comprising (i)from about 65 to about 75 parts by weight, based on the total weight ofthe polyamide mixture, of a nylon 6 resin; and (ii) from about 35 toabout 25 parts by weight, based on the total weight of the polyamidemixture, of a nylon 6/12 resin; (b) a diorganopolysiloxane gum having aplasticity of at least 30 and having an average of at least two alkenylgroups in its molecule, wherein the weight ratio of thediorganopolysiloxane gum to the polyamide resin(s) ranges from about40:60 to about 75:25; (c) a compatibilizer selected from the group of:i. a coupling agent having a molecular weight of less than 800 whichcontains at least two groups independently selected from ethylenicallyunsaturated group, epoxy, anhydride, silanol, carboxyl, oxazoline oralkoxy having 1 to 20 carbon atoms, in its molecule, ii. a functionaldiorganopolysiloxane having at least one group selected from epoxy,anhydride, silanol, carboxyl, amine, oxazoline or alkoxy having 1 to 20carbon atoms, in its molecule, or iii. a copolymer comprising at leastone diorganopolysiloxane block and at least one block selected frompolyamide, polyether, polyurethane, polyurea, polycarbonate orpolyacrylate; (d) an organohydrido silicon compound which contains anaverage of at least two silicon-bonded hydrogen groups in its molecule;and (e) a hydrosilation catalyst, components (d) and (e) being presentin an amount sufficient to cure component (b); and. (II) curingcomponent (b).